Does the statute of limitations begin to run when the factual predicate of the claim could have been discovered through the exercise of due diligence?

In this case, the statute of limitations began to run when the factual predicate of petitioner's claim could have been discovered through the exercise of due diligence. See Shelby, 391 F. 3d at 1065-66. Generally, when a petitioner is challenging a prison disciplinary decision, the factual predicate of a claim is discovered on the date the administrative appeal is denied. Id.; Mardesich v. Cate, 668 F.3d 1164, 1172 (9th Cir. 2012). Although his administrative appeal was denied on January 23, 2009, petitioner contends that he did not learn the factual predicate of his claim until August 27, 2009.